Correction support device and correction support program for optical character recognition result

ABSTRACT

A correction history recording unit that records region information of a correction site with respect to text data converted from an original image as correction history information, an accuracy calculation unit that calculates accuracy of optical character recognition for each of individual regions on a layout of the original image on the basis of the correction history information, a distribution image generation unit and a distribution image display unit which generate and display a distribution image in which a difference in magnitude of accuracy is shown as a difference in a display aspect for every individual region are included so as to generate and display the distribution image that is distinguished for every individual region by reflecting a tendency in which a character recognition rate in a certain region on a layout of the original image may decrease due to various cases including a format of an original document, a state of an OCR device, and the like.

CROSS REFERENCE TO RELATED APPLICATIONS

This application claims priority to Application No. 2018-204444 filed inJapan on 30 Oct. 2018. The entire contents of this application is herebyincorporated by reference.

BACKGROUND OF THE INVENTION Technical Field

The present invention relates to a correction support device and acorrection support program for an optical character recognition result,and particularly, to a technology for supporting correction work oferroneously recognized data in optical character recognition (OCR).

Related Art

A technology called optical character recognition (OCR) of recognizingcharacters included in an image and converting the characters into textdata (character codes capable of being used by a computer) is widelyused. Although characters as image data can be converted into charactersas text data, it is difficult to perform character recognition asaccurate as 100%. Accordingly, it is necessary to manually correcterroneously recognized characters. In the related art, a system thatsupports text data correction work based on a character recognitionresult of OCR is known (for example, refer to JP-A-11-102414).

In a character recognition correction device described inJP-A-11-102414, a document image (scanned image) that is an OCR outputsource is displayed, and when a region in the displayed document imageis selected, an OCR output text corresponding to the selected region isdisplayed in a pop-up menu. In addition, recognition accuracy parametersare determined with respect to document image regions corresponding towords in the OCR output, and a heat map is displayed to show respectiverecognition accuracy parameters (for example, highlighting with variouscolors).

Specifically, recognition accuracy parameters indicating possibilitythat recognition results relating to individual words are correctresults are compared with a plurality of threshold values, and a regionof a document image is displayed by determining display colors incorrespondence with the comparison results, thereby forming a heat mapof recognized words. For example, the recognition accuracy parametersare values which are assumed in advance in correspondence withcombinations of characters or the like on the assumption that acharacter of “rn” having an arbitrary font may be recognized as acharacter of “m” and a recognition accuracy parameter of 60% isdetermined for the character pair. As described above, the heat map isdisplayed on the document image on the basis of the recognition accuracyparameters of respective words to guide a user to the most problematicportion of the document image with respect to an OCR output.

SUMMARY OF THE INVENTION

A location in which a character with poor recognition accuracy in ascanned image is visualized by the heat map display described inJP-A-11-102414, and thus it is possible to easily understand a site towhich attention is to be paid in correction work on text data convertedon the basis of the character recognition result of the OCR.

In JP-A-11-102414, the heat map display is performed on the basis ofrecognition accuracy parameters determined as an erroneous recognitionpossibility with respect to individual words, but the cause foroccurrence of erroneous recognition is not limited to combinations ofcharacters or properties of words as described in JP-A-11-102414. Forexample, color characters or scratching of characters, slantedcharacters, clogging of character interval, shading of characters,contamination of a scanned image, handwritten characters, and the likecorrespond to cases where erroneous recognition is likely to occur.However, the technology described in JP-A-11-102414 has a problem thatthe heat map display cannot be performed in correspondence with variouscases where the erroneous recognition is likely to occur.

The invention has been made to solve the problem, and an object thereofis to provide a distribution image in which the degree of attention tobe paid in correction work on text data is distinguished for everyregion in correspondence with various cases where erroneous recognitionis likely to occur.

To solve the problem, in the invention, in a case where a specific sitein text data output as a result of optical character recognition withrespect to an original image is corrected by a user, it is detected thatthe correction site corresponds to which region on a layout of theoriginal image, and region information of the correction site isrecorded as correction history information. In addition, accuracy of theoptical character recognition is calculated for each of individualregions on the layout of the original image on the basis of thecorrection history information, and a distribution image in which adifference in magnitude of accuracy is shown as a difference in adisplay aspect for each of individual regions is generated anddisplayed.

According to the invention having the above-described configuration,whenever optical character recognition is performed with respect to anoriginal image, and a specific site in text data output as a result ofthe optical character recognition is corrected by a user, regioninformation indicating that the correction site corresponds to whichregion on a layout of the original image is sequentially recorded ascorrection history information. Here, a character recognition rate in acertain region on the layout of the original image may decrease due tovarious cases including a format of an original document before theoriginal image is generated by optical reading (scanning), a state of anapparatus that scans the original document and generates the originalimage, and the like. In this case, the number of times of correction oftext data in the certain region on the original image increases, and thenumber of times of correction of text data in the other region tends todecrease. According to the invention, accuracy of the optical characterrecognition that reflects such tendency is calculated for each ofindividual regions on the layout of the original image, and adistribution image, in which a difference in magnitude of the accuracyis shown as a difference in a display aspect for each of individualregions, is generated. Accordingly, according to the invention, it ispossible to provide a distribution image in which the degree ofattention to be paid in correction work on text data is distinguishedfor every region in correspondence with various cases where erroneousrecognition is likely to occur.

BRIEF DESCRIPTION OF THE DRAWINGS

FIG. 1 is a block diagram illustrating a functional configurationexample of a character recognition apparatus including a correctionsupport device according to a first embodiment.

FIG. 2 is a diagram illustrating a hardware configuration example of thecharacter recognition apparatus.

FIGS. 3A and 3B are views illustrating an example of individual regionswhich are set on an original image.

FIG. 4 is a view illustrating an example of a distribution image that isdisplayed on a display device under control of a distribution imagedisplay unit.

FIG. 5 is a block diagram illustrating a functional configurationexample of a character recognition apparatus including a correctionsupport device according to a second embodiment.

FIGS. 6A and 6B are views illustrating an example of information that isdisplayed on the display device under control of a recognition resultdisplay unit.

FIG. 7 is a block diagram illustrating a functional configurationexample of a character recognition apparatus including a correctionsupport device according to a third embodiment.

FIGS. 8A and 8B are views illustrating an example of information that isdisplayed on the display device under control of a correction screendisplay unit.

FIGS. 9A and 9B are views illustrating another example of informationthat is displayed on the display device under control of the correctionscreen display unit.

DETAILED DESCRIPTION OF THE INVENTION First Embodiment

Hereinafter, a first embodiment of the invention will be described withreference to the accompanying drawings. FIG. 1 is a block diagramillustrating a functional configuration example (including a hardwareconfiguration at a part) of a character recognition apparatus 100including an optical character recognition result correction supportdevice (hereinafter, simply referred to as “correction support device”)10A according to the first embodiment. FIG. 2 is a diagram illustratinga hardware configuration example of the character recognition apparatus100. The correction support device 10A is a device that supportcorrection work on text data converted from characters included in anoriginal image through optical character recognition.

As illustrated in FIG. 2, the character recognition apparatus 100includes an operation unit 101, a scanner 102, an OCR device 103, adisplay device 104, a microcomputer 105, and a storage device 106.

Examples of the operation unit 101 include a keyboard, a mouse, a touchpanel, and the like, and a user operates these devices to give variousinstructions to the character recognition apparatus 100. The scanner 102is an optical reading device, optically reads an original document on apaper medium such as a document, and converts the original document intoimage data. The image data generated by the scanner 102 corresponds toan “original image” in claims.

The OCR device 103 recognizes characters included in the original imagegenerated by the scanner 102, and converts characters as an image(hereinafter, referred to as “character image”) into a character code(hereinafter, referred to as “character text”) to generate text data.For example, the display device 104 is a display such as a liquidcrystal display device, and an organic EL display device, and displaysvarious pieces of information. For example, the display device 104displays the original image generated by the scanner 102, the text datagenerated by the OCR device 103, or the like. In addition, the displaydevice 104 displays various screens to be described later.

The microcomputer 105 controls operations of the operation unit 101, thescanner 102, the OCR device 103, and the display device 104. Inaddition, the microcomputer 105 controls an operation of the correctionsupport device 10A illustrated in FIG. 1. The storage device 106 is anon-volatile storage medium that stores various pieces of data, andexamples thereof include a hard disk, a semiconductor device, and thelike.

Next, description will be given of a functional configuration of thecharacter recognition apparatus 100 including the correction supportdevice 10A according to the first embodiment. As illustrated in FIG. 1,as a functional configuration, the character recognition apparatus 100includes a correction history recording unit 11, an accuracy calculationunit 12, a distribution image generation unit 13, a distribution imagedisplay unit 14, a correction history storage unit 15, an original imagestorage unit 21, a text storage unit 22, and a correction processingunit 23. Among the units, the correction history recording unit 11, theaccuracy calculation unit 12, the distribution image generation unit 13,the distribution image display unit 14, and the correction historystorage unit 15 are functional configurations provided in the correctionsupport device 10A according to the first embodiment.

The correction history recording unit 11, the accuracy calculation unit12, the distribution image generation unit 13, the distribution imagedisplay unit 14, and the correction processing unit 23 actually includea CPU, a RAM, a ROM, or the like of the microcomputer 105 illustrated inFIG. 2, and are realized when a program stored in the RAM or the ROM, ora recording medium such as a hard disk and a semiconductor memoryoperates. Note that, the entirety or a part of the functions may berealized by hardware or a digital signal processor (DSP). The correctionhistory storage unit 15, the original image storage unit 21, and thetext storage unit 22 are functional configurations provided in thestorage device 106 illustrated in FIG. 1.

The original image storage unit 21 stores the original image (image dataof a read original document such as a document or the like) generated bythe scanner 102. Here, the original image storage unit 21 stores oneoriginal image with respect to one sheet of original document.

The text storage unit 22 stores the text data generated by the OCRdevice 103. Here, the text storage unit 22 stores one page of text datawith respect to one original image. The one page of text data has layoutinformation that imitates a layout of the original image, and in the onepage of text data, a character text is disposed at approximately thesame position as that of a character image included in the originalimage.

The text data stored in the text storage unit 22 includes associationinformation that correlates position information of the character imagein the original image (for example, coordinate values in atwo-dimensional coordinate plane with one corner of the original imageset as the origin), and the character text converted from the characterimage. That is, when the OCR device 103 recognizes the character imageincluded in the original image and converts the character image into thecharacter text, position information of the character image in theoriginal image is acquired, and the position information is stored inthe text storage unit 22 in correlation with the character text.

The correction processing unit 23 corrects the text data stored in thetext storage unit 22 in correspondence with an instruction from a user.It is difficult to set a recognition rate (a probability of conversioninto a correct character text without erroneous recognition) in thecharacter recognition by the OCR device 103 to 100%, and there is apossibility that an incorrect character text due to erroneousrecognitions may be included in the text data. For example, a userdisplays the text data on a screen of the display device 104, comparesthe text data with an original document on hand to find an erroneouslyrecognized character text, and operates the operation unit 101 toperform necessary correction.

In a case where correction of the character text is performed by thecorrection processing unit 23, the text data is updated in a state inwhich the correction is reflected, and the updated text data is storedin the text storage unit 22. At this time, the text data before updateis overwritten with the updated text data.

In a case where a character text (corresponding to “specific site” inclaims) specified in the text data (corresponding to “text data outputas a result of optical character recognition” in claims) stored in thetext storage unit 22 is corrected by a user, the correction historyrecording unit 11 detects that the correction site corresponds to whichregion in the layout of the original image, and records regioninformation of the correction site in the correction history storageunit 15 as correction history information.

As described above, the text data includes the association informationthat correlates the position information of the character image in theoriginal image, and the character text converted from the characterimage. Accordingly, in a case where any character text is corrected bythe correction processing unit 23, it is possible to acquire positioninformation of the character image in the original image due to theassociation information corresponding to the character text. Thecorrection history recording unit 11 detects the position information asregion information of a correction site, and causes the correctionhistory storage unit to store the region information that is detected ascorrection history information.

In a case where a plurality of pieces of text data are stored in thetext storage unit 22 by subjecting a plurality of sheets of originaldocuments to the OCR processing, and necessary correction is performedby the correction processing unit 23 with respect to respective piecesof text data, a plurality of pieces of region information indicatingcorrection sites in the pieces of text data are sequentially stored inthe correction history storage unit 15. Here, when the same site in aplurality of pieces of text data is corrected, region informationindicating the same correction site is accumulated in the correctionhistory storage unit 15.

The accuracy calculation unit 12 calculates accuracy of the opticalcharacter recognition for each of individual regions on the layout ofthe original image on the basis of the correction history informationstored in the correction history storage unit 15. Here, the individualregions represent a plurality of small regions which are set in a wholeregion of the original image.

FIGS. 3A and 3B are views illustrating an example of individual regions.As illustrated in FIG. 3A, the individual regions may be set torespective divided regions in a case where the whole region of theoriginal image is divided into m pieces in a vertical direction and isdivided into n pieces in a horizontal direction. A division method isarbitrary, and thus the size of the divided regions can be designed inan arbitrary manner. In a case where the individual regions are set asin FIG. 3A, the respective individual regions become continuous regionsadjacent to each other.

In addition, as illustrated in FIG. 3B, the individual regions may beset to non-continuous small regions which are set to be distributed inthe whole region of the original image. For example, regions in whichthe character image included in the original image exists can be set asthe individual regions. In the case of a plurality of original documentshaving a standard format are subjected to the OCR processing, in aplurality of original images generated from the original documents,regions of the character image exist at the same position. The regionsof the character image may exist at discrete positions in the originalimage, and the regions may be set as the individual regions.

The accuracy calculation unit 12 calculates accuracy of the opticalcharacter recognition for each of the individual regions set on thelayout of the original image on the basis of the correction historyinformation stored in the correction history storage unit 15. Theaccuracy represents an index that is calculated on the basis of asituation in which correction of the character text at a positioncorresponding to the individual region has been performed to a certainextent. The larger the number of times of correction performed is, thesmaller a value of the accuracy is, and the smaller the number of timesof correction performed is, the larger the value of the accuracy is.

For example, the accuracy calculation unit 12 calculates a reciprocal ofa ratio of the number of correction performed as the accuracy with thenumber of text data stored in the text storage unit 22 set as aparameter. The number of times of correction of the character text inthe individual region can be obtained by counting the number ofcorrection sites in which the same region information is stored on thebasis of the region information of the correction sites which is storedin the correction history storage unit 15. Note that, in a case wherethe number of times of correction performed is zero, a value becomes ∞when a reciprocal is taken, but a value of the accuracy in this case maybe set to ∞, or may be set to a predetermined highest value.

Note that, here, description has been made on the assumption that theaccuracy is calculated with the number of text data stored in the textstorage unit 22 set as the parameter, but the invention is not limitedthereto. For example, the accuracy may be calculated by setting thenumber of text data generated from an original document having a certainspecific standard format in the text data stored in the text storageunit 22 is set as the parameter. In this case, for example, when theoriginal document is read by the scanner 102 and the text data isgenerated by the OCR device 103, a situation in which the originaldocument is an original document having a specific standard format isdesignated by an operation of the operation unit 101, and text datagenerated through the designation is stored in the text storage unit 22in a state capable of being identified from the other text data. In thiscase, it is possible to calculate accuracy with respect to text datagenerated from an original document having a specific standard format.

Here, in a case where the individual regions are set to positions ofcharacter images as in FIG. 3B, a position of each of the individualregions and a position at which each character text is disposed matcheach other. Accordingly, a value obtained by counting correction sitesin which the same region information is stored on the basis of regioninformation of the correction sites stored in the correction historystorage unit 15 (the number of times of correction of the character textin the region information) becomes a value that can be used as thenumber of times of correction of the character text in a correspondingindividual region, and it is possible to calculate the accuracy forevery individual region on the basis of the above-described situation.

On the other hand, in a case where the continuous divided regions areset as the individual regions as in FIG. 3A, it cannot be said that aposition of each of the individual regions and a position at which eachcharacter text is disposed (that is, a position that is indicated byregion information of a correction site which is stored in thecorrection history storage unit 15) match each other. In this case,accuracy calculated on the basis of the region information of thecorrection site may be regarded as accuracy of one or a plurality ofindividual regions of which at least a part overlaps the positionindicated by the region information of the correction site.

The distribution image generation unit 13 generates a distribution imagein which a difference in magnitude of accuracy is shown as a differencein a display aspect for each of the individual regions on the basis ofaccuracy calculated by the accuracy calculation unit 12 for each of theindividual regions. For example, with respect to the whole layout of theoriginal image, the distribution image generation unit 13 generates awhole distribution image in which a difference in magnitude of accuracyis shown as a difference in a display aspect for each of the individualregions on the basis of accuracy calculated by the accuracy calculationunit 12 for each of the individual regions included in the whole layout.

For example, the display aspect that is changed for each of theindividual regions is a display color. For example, the distributionimage generation unit 13 classifies the magnitude of the accuracy intothree kinds in accordance with two threshold values, and generatessub-distribution images indicating the individual regions with differentdisplay colors in correspondence with the classification.

Specifically, an individual region pertaining to a classification inwhich the accuracy is the largest is indicated by a blue color, anindividual region pertaining to a classification in which the accuracyis approximately intermediate is indicated by a yellow color, and anindividual region pertaining to a classification in which the accuracyis the smallest is indicated by a red color or the like. The individualregion pertaining to the classification in which the accuracy is thelargest may be set to a colorless region (the same color as a backgroundcolor). Note that, as a display aspect that is changed for everyindividual region, a display density of the same color or the type ofshading, or the like may be used instead of the display color.

Here, description has been given of an example in which the distributionimage generation unit 13 generates whole distribution imagescorresponding to the whole layout of the original image, but theinvention is not limited thereto. For example, with respect to a partialregion designated in the whole layout of the original image by anoperation of the operation unit 101, the distribution image generationunit 13 may generate a partial distribution image in which a differencein magnitude of accuracy is shown as a difference in a display aspectfor each of the individual regions on the basis of accuracy calculatedby the accuracy calculation unit 12 for each of the individual regionsincluded in the designated partial region.

The distribution image display unit 14 causes the display device 104 todisplay the distribution image generated by the distribution imagegeneration unit 13. For example, when a user operates the operation unit101 to give an instruction for the correction support device 10A todisplay the distribution image, the distribution image generation unit13 generates the distribution image, and the distribution image displayunit 14 causes the display device 104 to display the generateddistribution image.

Here, the distribution image display unit 14 may display a colordistribution image (heat map image) in which a display color is changedfor every individual region, or may subject the color distribution imageto translucentizing processing and display the color distribution imagein a manner of being superimposed on the original image. In addition,the distribution image generation unit 13 may perform processing forapplying a color distribution to the original image to generate aprocessed image including the color distribution on the original imageinstead of the aspect in which the distribution image display unit 14subjects the color distribution image to the translucentizing processingand superimposes the color distribution image on the original image.

FIG. 4 is a view illustrating an example of the distribution image thatis displayed on the display device 104. FIG. 4 illustrates an example ofthe whole distribution image (heat map image) that is displayed in acase where the individual regions are set as in FIG. 3A. In addition,FIG. 4 illustrates an example of a distribution image in which anindividual region pertaining to a classification in which the accuracyis the largest is set to a colorless region, and an individual regionpertaining to a classification in which the accuracy is approximatelyintermediate and an individual region pertaining to a classification inwhich the accuracy is the smallest are displayed with different colors.

A user can understand that accuracy of which region is low as a resultof reflection of a past correction history, that is, many erroneousrecognitions have occurred in which region at a glance when viewing thedistribution image. In a case where the user understands the region inwhich the many erroneous recognitions have occurred, when correction ofthe text data is performed by the correction processing unit 23, it ispossible to obtain a guide indicating which regions of the text datadisplayed on the display device 104 and the original document on handare preferable to be intensively confirmed, and it is possible toeffectively perform correction work.

Note that, as a case where the erroneous recognition in a certainspecific region increases even through a plurality of original documentswhich are different in character image content are subjected to the OCRprocessing, various factors can be considered. For example, in a casewhere an original document with a standard format is subjected to theOCR processing, with respect to a specific region, a characterrecognition rate in a certain region on the layout of the original imagemay decrease due to formats of the original document, from which theoriginal image is generated through scanning, such as a format in whichcharacters are in a color other than black, a format in which charactersare in a color close to a background color, a format in which charactersare slanted, and a format of handwritten characters.

In addition, regardless of whether or not the original document is anoriginal document with the standard format, the character recognitionrate in a certain region on the layout of the original image maydecrease due to a state of the scanner 102 or the OCR device 103, or thelike. For example, when the original document is a document that isstamped out by FAX, characters in a specific region may be frequentlyscratched. In addition, when a document platen of the scanner 102 isscratched or contaminated, a dot group having a fixed shape may beformed in a specific region on the original image.

In this case, relatively many erroneous recognitions occur in a certainregion on the original image, and the number of times of correction of acharacter text converted from a character image in the region tends toincrease, and the number of times of correction of a character textconverted from a character image in a region other than the certainregion tends to decrease. According to this embodiment, accuracy thatreflects the tendency is calculated for each of individual regions on alayout of an original image, and a distribution image in which adifference in magnitude of accuracy is shown as a difference in adisplay color for every individual region is generated. Accordingly,according to this embodiment, it is possible to provide a user with adistribution image in which the degree of attention to be paid incorrection work on text data is distinguished for every region incorrespondence with various cases where erroneous recognition is likelyto occur. The user views the distribution image, and can effectivelyperform correction work on the text data.

Second Embodiment

Next, a second embodiment of the invention will be described withreference to the accompanying drawings. FIG. 5 is a block diagramillustrating a functional configuration example (including a hardwareconfiguration at a part) of the character recognition apparatus 100including a correction support device 10B according to the secondembodiment. Note that, in FIG. 5, a constituent element to which thesame reference numeral as the reference numeral illustrated in FIG. 1 isgiven has the same function, and thus redundant description will beomitted.

As illustrated in FIG. 5, the correction support device 10B according tothe second embodiment further includes a recognition result display unit16 as a functional configuration. The recognition result display unit 16actually includes a CPU, a RAM, a ROM, or the like of the microcomputer105 illustrated in FIG. 2, and is realized when a program stored in theRAM or the ROM, or a recording medium such as a hard disk and asemiconductor memory operates.

The recognition result display unit 16 causes the display device 104 todisplay the original image stored in the original image storage unit 21,receives designation of an arbitrary partial region on the displayedoriginal image, and displays partial text data that is a result ofoptical character recognition in the designated partial region as anadditional screen. Here, the designation of the arbitrary partial regionon the displayed original image is performed through an operation of theoperation unit 101 by a user. In addition, the partial text data isgenerated by using the text data stored in the text storage unit 22.

As described above, the text data stored in the text storage unit 22 haslayout information that imitates the layout of the original image.Accordingly, when receiving the designation of the arbitrary partialregion on the original image, the recognition result display unit 16 canspecify a region on the text data corresponding to the partial regiondesignated on the original image from the layout information, and cangenerate text data of the specified partial region as partial text data.The recognition result display unit 16 causes the display device 104 todisplay the partial text data generated as described above. For example,the partial text data is pop-up displayed in a manner of beingsuperimposed on the original image displayed on the display device 104.

When causing the display device 104 to display the partial text data,the recognition result display unit 16 performs display in which adifference in magnitude of accuracy is shown as a difference in adisplay aspect for every text region corresponding to each of theindividual regions on additional screen display (pop-up display) on thebasis of the accuracy calculated by the accuracy calculation unit 12 foreach of the individual regions included in the designated partialregion.

The text regions corresponding to the individual regions representsregions set on the text data as in the individual regions set on theoriginal image. For example, in a case where the individual regions areset on the original image as in FIG. 3A, the individual regions set onthe text data in a similar manner to FIG. 3A are the text regions. Onthe other hand, in a case where the individual regions are set on theoriginal image as in FIG. 3B, the individual regions set on the textdata in a similar manner to FIG. 3B are the text regions. For example,the individual text regions are set as a text box, and a display colorin the box is changed in correspondence with accuracy. Note that, amethod of setting the display color with respect to the text regions isnot limited thereto.

FIGS. 6A and 6B are views illustrating an example of information that isdisplayed on the display device 104 under control of the recognitionresult display unit 16. In FIGS. 6A and 6B, a region indicated by areference numeral 60 is a region (for example, the entirety of a displayscreen of the display device 104) in which the original image is shown.A region indicated by a reference numeral 61 is a partial regiondesignated on the original image by a user. A region indicated by areference numeral 62 is a pop-up screen of the partial text datadisplayed in correspondence with the partial region designated on theoriginal image. Note that, here, description of specific drawing of theoriginal image in the region 60 is omitted. In addition, description ofthe pop-up screen 62 is simplified.

Here, an example of the pop-up screen 62 displayed in the case ofsetting the individual regions as in FIG. 3A is illustrated. That is, onthe basis of accuracy calculated by the accuracy calculation unit 12with respect to individual regions included in the partial region 61designated on the original image among the individual regions set withrespect to the whole region of the original image as in FIG. 3A, therecognition result display unit 16 generates a distribution image inwhich a display color is changed for every text region corresponding tothe individual regions, and displays the distribution image on thepop-up screen 62.

A user can directly correct, on the pop-up screen 62, a character texton the partial text data displayed on the pop-up screen 62. At thistime, on the pop-up screen 62, an individual text region as a result ofreflection of a past correction history is displayed in each color, andthus the user can understand that accuracy of which text region is low,that is, many erroneous recognitions have occurred in which text regionat a glance. According to this, when performing correction of thepartial text data on the pop-up screen 62 by the correction processingunit 23, the user can obtain a guide indicating which regions on thepop-up screen 62 and an original document on hand are preferable to beintensively confirmed, and can effectively perform correction work.

Note that, display and non-display of the pop-up screen 62 (anon-display state illustrated in FIG. 6A and a display state illustratedin FIG. 6B) may be switched from each other in a toggle manner through aspecific operation (for example, an operation of a specific key on akeyboard, or the like) in the operation unit 101. In this case, whenperforming correction of the partial text data displayed on the pop-upscreen 62, it is not necessary to compare the partial text data with theoriginal document on hand, and it is possible to compare the partialtext data and the original image while switching display and non-displayof the pop-up screen 62 in a toggle manner, and thus it is possible tomore effectively perform correction work.

Third Embodiment

Next, a third embodiment of the invention will be described withreference to the accompanying drawings. FIG. 7 is a block diagramillustrating a functional configuration example (including a hardwareconfiguration at a part) of the character recognition apparatus 100including a correction support device 10C according to the thirdembodiment. Note that, in FIG. 7, a constituent element to which thesame reference numeral as the reference numeral illustrated in FIG. 1 isgiven has the same function, and thus redundant description will beomitted.

As illustrated in FIG. 7, the correction support device 10C according tothe third embodiment further includes a correction screen display unit17 as a functional configuration. The correction screen display unit 17actually includes a CPU, a RAM, a ROM, or the like of the microcomputer105 illustrated in FIG. 2, and is realized when a program stored in theRAM or the ROM, or a recording medium such as a hard disk and asemiconductor memory operates.

The correction screen display unit 17 receives designation of anarbitrary partial region on the original image, and displays acorrection screen in which a partial original image of the partialregion that is designated, and partial text data that is a result ofoptical character recognition in the designated partial region arearranged in parallel. Here, the designation of the arbitrary partialregion on the original image is performed through an operation of theoperation unit 101 by a user. In addition, the partial original image isgenerated by using the original image stored in the original imagestorage unit 21, and the partial text data is generated by using thetext data stored in the text storage unit 22.

The correction screen display unit 17 performs display in which adifference in magnitude of accuracy is shown as a difference in adisplay aspect for each of individual regions on the original image ofthe partial region on the correction screen on the basis of the accuracycalculated by the accuracy calculation unit 12 for each of theindividual regions included in the designated partial region. Forexample, the correction screen display unit 17 generates a colordistribution image in which a display color is changed for everyindividual region in correspondence with the accuracy, subjects thecolor distribution image to translucentizing processing, and displaysthe color distribution image in a manner of being superimposed on thepartial original image. Alternatively, a partial original image in whicha display color is changed for every individual region in correspondencewith the accuracy may be generated and displayed.

FIGS. 8A and 8B are views illustrating an example of informationdisplayed on the display device 104 under control of the correctionscreen display unit 17. Note that, in FIGS. 8A and 8B, the samereference numeral will be given to the same element as the elementillustrated in FIGS. 6A and 6B. FIG. 8A illustrates the same state as inFIG. 6A.

FIG. 8B illustrates a correction screen 80 that is displayed incorrespondence with a partial region 61 designated on the originalimage. In the correction screen 80, a partial original imagecorresponding to the partial region 61 designated on the original imageby a user is displayed in a left region 81. In addition, partial textdata corresponding to the designated partial region 61 is displayed in aright region 82. Here, with regard to the partial original imagedisplayed in the left region 81, display in which a difference inmagnitude of accuracy calculated for each of individual regions includedin the partial region 61 is shown as a difference in a display color isperformed. Note that, in the partial text data displayed in the rightregion 82, the difference in the magnitude of the accuracy may be shownas the difference in the display color for every text region.

Here, a display example in the case of setting the individual region asin FIG. 3A is illustrated. Specifically, the correction screen displayunit 17 generates a distribution image in which a display color ischanged for each of individual regions on the basis of accuracycalculated by the accuracy calculation unit 12 with respect toindividual regions included in the partial region 61 designated on theoriginal image among the individual regions set with respect to thewhole region of the original image as in FIG. 3A, subjects thedistribution image to translucentizing processing, and displays thecolor distribution image in a manner of being superimposed on thepartial original image. Alternatively, a partial original image in whicha display color is changed for every individual region in correspondencewith the accuracy may be generated and displayed.

A user can directly correct a character text on the partial text datadisplayed in the right region 82 of the correction screen 80. At thistime, in the left region 81 of the correction screen 80, the partialoriginal image is displayed in a state in which individual regions aredistinguished as a result of reflection of a past correction history,and thus the user can understand that accuracy of which region is low,that is, many erroneous recognitions have occurred in which region at aglance. In addition, the user can perform correction while comparing thepartial original image and the partial text data on one screen, and thusit is possible to significantly improve efficiency of correction work.

Note that, a method of arranging the partial original image of thepartial region designated on the original image, and the partial textdata corresponding to the designated partial region in parallel is notlimited to the example illustrated in FIGS. 8A and 8B. For example, inFIGS. 8A and 8B, the partial original image and the partial text data isdisplayed in parallel in a horizontal direction, but may be displayed inparallel in a vertical direction.

In addition, FIGS. 8A and 8B illustrates an example in which the partialoriginal image and the partial text data are displayed in parallel in astate of maintaining the original layout, but display may be performedby changing the layout for easy viewing. For example, in a case wherethe individual regions are set with respect to the whole region of theoriginal image as in FIG. 3A, individual regions including a characterimage are extracted among the individual regions included in thedesignated partial region 61, and extracted individual regions 91 andtext region 92 corresponding to the individual regions 91 may bedisplayed in parallel as illustrated in FIGS. 9A and 9B. This is alsoapplicable to a case where the individual regions are set as in FIG. 3B.Note that, in FIGS. 9A and 9B, in the designated partial region 61, onlyregions including the entirety of the individual regions are extractedand arranged.

Note that, the second embodiment and the third embodiment may be appliedin combination.

In addition, any of the first to third embodiments merely illustrate anexample of embodiment when performing the invention, and it should notbe understood that the technical scope of the invention is limited bythe embodiments. That is, the invention can be carried out in variousembodiments without being departed from the gist or importantcharacteristics.

What is claimed is:
 1. A correction support device for an opticalcharacter recognition result, the correction support device supportingcorrection work on text data converted from characters included in anoriginal image by optical character recognition, the correction supportdevice comprising: a correction history recording unit that detects thata correction site corresponds to which region on a layout of theoriginal image in a case where a specific site in the text data outputas a result of the optical character recognition is corrected by a user,and records region information of the correction site as correctionhistory information; an accuracy calculation unit that calculatesaccuracy of the optical character recognition for each of individualregions on the layout of the original image on the basis of thecorrection history information that is recorded by the correctionhistory recording unit; a distribution image generation unit thatgenerates a distribution image in which a difference in magnitude of theaccuracy is shown as a difference in a display aspect for each of theindividual regions on the basis of the accuracy calculated by theaccuracy calculation unit for each of the individual regions; and adistribution image display unit that displays the distribution imagegenerated by the distribution image generation unit.
 2. The correctionsupport device for an optical character recognition result according toclaim 1, wherein with respect to the whole layout of the original image,the distribution image generation unit generates a whole distributionimage in which a difference in magnitude of accuracy is shown as adifference in a display aspect for each of individual regions on thebasis of the accuracy calculated by the accuracy calculation unit foreach of the individual regions included in the whole layout.
 3. Thecorrection support device for an optical character recognition resultaccording to claim 1, wherein with respect to a partial regiondesignated in the whole layout of the original image, the distributionimage generation unit generates a partial distribution image in which adifference in magnitude of accuracy is shown as a difference in adisplay aspect for each of individual regions on the basis of theaccuracy calculated by the accuracy calculation unit for each of theindividual regions included in the designated partial region.
 4. Thecorrection support device for an optical character recognition resultaccording to claim 1, further comprising: a recognition result displayunit that displays the original image, receives designation of anarbitrary partial region on the displayed original image, and displayspartial text data that is a result of the optical character recognitionin the designated partial region as an additional screen, wherein therecognition result display unit performs display in which a differencein magnitude of accuracy is shown as a difference in a display aspectfor every text region corresponding to each of individual regions onadditional screen display on the basis of the accuracy calculated by theaccuracy calculation unit for each of the individual regions included inthe designated partial region.
 5. The correction support device for anoptical character recognition result according to claim 1, furthercomprising: a correction screen display unit that receives designationof an arbitrary partial region on the original image, and displays acorrection screen in which a partial original image of the partialregion that is designated, and partial text data that is a result of theoptical character recognition in the designated partial region arearranged in parallel, wherein the correction screen display unitperforms display in which a difference in magnitude of accuracy is shownas a difference in a display aspect for each of individual regions orevery text region corresponding to the individual region on the partialoriginal image or the partial text data of the correction screen on thebasis of the accuracy calculated by the accuracy calculation unit foreach of the individual regions included in the partial region that isdesignated.
 6. A correction support program, stored on a non-transitorycomputer readable medium, for an optical character recognition result,the program providing a function of supporting correction work on textdata converted from characters included in an original image by opticalcharacter recognition, the program causing a computer to function as: acorrection history recording unit that detects that a correction sitecorresponds to which region on a layout of the original image in a casewhere a specific site in the text data output as a result of the opticalcharacter recognition is corrected by a user, and records regioninformation of the correction site as correction history information; anaccuracy calculation unit that calculates accuracy of the opticalcharacter recognition for each of individual regions on the layout ofthe original image on the basis of the correction history informationthat is recorded by the correction history recording unit; adistribution image generation unit that generates a distribution imagein which a difference in magnitude of the accuracy is shown as adifference in a display aspect for each of the individual regions on thebasis of the accuracy calculated by the accuracy calculation unit foreach of the individual regions; and a distribution image display unitthat displays the distribution image generated by the distribution imagegeneration unit.